SOUTH BURLINGTON — A spokesman for the U.S. Transportation Security Agency said Tuesday it’s likely a Vermont man who tried to carry a gun onto a plane at the Burlington International Airport will face a fine of up to $3,000.

But Burlington police said it’s unlikely the man will be criminally charged.

Police were convinced that it was “complete, embarrassing error” when the 46-year-old man, whom he declined to name, approached the security checkpoint with a bag containing the gun, Deputy Police Chief Bruce Bovat said.

Mike McCarthy of the TSA office in Boston said the federal agency issues such civil fines “whenever a firearm is caught.”

If the weapon is unloaded, as was the case in the Vermont incident, the fine ranges between $1,500 and $3,000, McCarthy said.

Loaded weapons bring higher fines, he added.

The man gave what McCarthy described as the most common explanation TSA agents hear when a firearm is discovered — that he forgot he had the weapon with him.

McCarthy said the fines are part of the TSA’s effort to educate the public of the importance of checking luggage “and knowing what the rules are before they get to the checkpoint.”